Black spot mould

To completely eradicate the problem you will need to identify the cause of the mould. Its likely due to excess moisture or condensation which could be down to a number of things i.e poor ventilation, external water leaking into property [guttering or downpipe overflow/leak, damaged flashing, improper weep vents, Rising damp], internal leak from plumbing issues etc and without seeing in person is nearly impossible to pin point, but this will need to be rectified to avoid further mould issues reoccurring. If its purely down to condensation, say in a toilet or bathroom or around windows this can be easier to rectify with steps like using extractor fan, opening windows, wiping down any splashes and excess water, ensuring doors/windows are sealed correctly, ensuring any tile grout is in good condition etc. Other causes may need a professional diagnosis. Just Painting over with ‘mould-resistant’ or ‘anti-fungal’ paints without treating then cause will only mask the problem & be a temporary fix with the mould almost certainly re-appearing in time. My advise would be to find and fix the cause of damp and then thoroughly clean the area and surrounding area once remedied, either with a mild detergent or some designated ‘mould remover’. Allow to fully dry, then use a specialist damp seal on the affected area’s. Then finally for the finishing coats opt for a mould resistant paint. Hope this helps.

Black spot mould is not caused by any damp condition of the building, it is only condensation and poor air exchange. Buy a digital thermal hygrometer off the internet for about £12.00. If the humidity rises to higher than 63% it’s time to ventilate. Do this by opening a window on opposite sides of the property simultaneously,for 20 minutes only , repeat to a maximum of twice a day in winter . Mould can be treated with distilled white vinegar, 3% hydrogen peroxide or Ronseal 3IN1 mould killer. This is a long process of eradication with some lifestyle changes to reduce moisture input to the house but you’ll win .

You can get the area cleaned and sterilised to remove what's there now but then you have to find out why it is there. It could be a number of things such as lack of ventilation or a cold spot in that specific area. When warm air hits the cold spot it becomes a dew point at that area. A dew point is when the warm air hits cold and turns into moisture. The mould spores feed off the moisture and multiply. Without looking at it and the property I can only say what may be the issue but lack of adequate ventilation is a big contributor to it.

Mould is always due to poor ventilation, and this leads to high humidity and condensation and then this leads to mould. Never paint over mould, this just hides the problem for a short while. Always clean up mould, bleach is good, but then make sure you have good ventilation and good extraction in kitchen and bathroom. This will usually cure most mould issues.